I was never treated that way by any of the religious people I met and it's against city, county, state, and federal law to do things like that. I'm not saying that you wont ever find discrimination based on religion, that happens, but it's never blatant, in your face stuff. You simply don't get a job and they'll justify it by saying you didn't meet the requirements. But honestly, since Salt Lake City has one of the largest gay communities of any U.S. city it's hard to believe that the people there are actively discriminating over religious beliefs.
In general I ran in to problems that are more common with bigger cities (I lived just north of Salt Lake City in that big urban strip along the Salt Lake) more than problems inspired by religious differences. Salt Lake City has become a bastion of leftist social action and they are very militant about their views. Like most large cities in the U.S., they control the politics of their respective states, not the rural people that, quite often, outnumber them.
Hell, here in Montana everybody knows that Missoula is progressive and that all the crazy crap comes from there, unfortunately Bozeman and Helena aren't far behind. If there is a university in the town then the larger it is the better the chance that the town will be progressive.